ANSI WELDING NECK FLANGE 1-standards:ASTM,BN API,etc 2-material:carbon steel, ... neck, slip-on, threaded, lap-joint, socket welding and blind2>Manufacturing standards: API, ANSI, BS, JIS, UNI, MSS and SP3>Size ... steel pipe, elbow, tri -elbow, different-diameter pipe, bebded pipe, flange, etc. The main products have been awarded by provicne and ...